Canyonlands National Park - Geology

Canyonlands National Park is a showcase of geology. In each of the districts, visitors can see the remarkable effects of millions of years of erosion on a landscape of sedimentary rock.

DEPOSITION

For hundreds of millions of years, material was deposited from a variety of sources in what is now Canyonlands National Park. As movements in the earth’s crust altered surface features and the North American continent migrated north from the equator, the local environment changed dramatically.

Over time, southeast Utah was flooded by oceans, crisscrossed by rivers, covered by mudflats and buried by sand. The climate has resembled a tropical coast, an interior desert, and everything in between. Layer upon layer of sedimentary rock formed as buried materials were cemented by precipitates in ground water. Each layer contains clues, like patterns or fossils, that reveal its depositional environment. For example, the red and white layers of Cedar Mesa Sandstone occur where floods of iron-rich debris from nearby mountains periodically inundated coastal dunes of white sand. Only a trace of iron is needed to color a rock red.

It is difficult to imagine such major changes and the time scale they spanned. Equally surprising is the fact that all of these rock layers were flat when they were deposited. Only recently, speaking in geologic time, have these layers eroded to form the remarkable landscape seen today.

EROSION

Until about 15 million years ago, most of the canyonlands area was near sea level. Local uplifts and volcanic activity had created features like Capitol Reef's Waterpocket Fold and the La Sal Mountains near Moab, but then movements in the earth's crust caused the whole area to rise. Today, the average elevation is over 5,000 feet above sea level.

The uplifting of this region, known as the Colorado Plateau, marked a shift from a depositional environment to one of erosion. The Colorado and Green rivers began to downcut and are now entrenched in canyons over 2,000 feet deep. Sediment-filled storm run-off drains into these rivers, scouring the surrounding landscape of into a network of tributary canyons, pour-offs and washes.

How sedimentary rock weathers depends largely on its exposure to water. An erosion- resistant caprock of White Rim Sandstone may protect a weaker layer of shale until only a thin spire remains. Examples of such "standing rocks" can be seen in both the Island in the Sky and the Maze districts. In addition to floods, the expansion of freezing water is a powerful erosive force. As ice loosens surface material and widens cracks, everything becomes more vulnerable to the next big storm.

Another significant factor in the shaping of Canyonlands is the Paradox Formation, a layer of sea water evaporates from the Pennsylvanian Period. Deeply buried, the salts in this layer can liquefy under the weight of the overlying rock, flowing, like toothpaste, away from the source of greatest overburden. In response, the upper layers may bow up, creating a salt dome, or erode and collapse, creating a salt valley.

This phenomenon is especially visible in the Needles, where parallel cracks or "joints" formed in the surface rock as buried layers slumped toward Cataract Canyon. These cracks are perpendicular to an older system of cracks created by the "Monument Uplift." The resulting crosshatched pattern of joints has eroded so that great blocks of sandstone have been reduced to thin spires of rock.

THE NEEDLES

The Needles are a series of spires located to the southwest of Squaw Flat campground that surround the Chesler Park area of the Needles District. They are formed out of a resistant red and white sandstone layer called Cedar Mesa Sandstone which makes up most of the rock features in the Needles District. This 245 to 286 million year old layer was once a dune field on the eastern edge of a shallow sea that covered what is California, Nevada and western Utah today. Sand was blown in from this direction and formed the white bands in the Cedar Mesa Sandstone. The red bands came from sediment carried down by streams from a mountainous area near where Grand Junction is today. These layers of sand were laid down on top of each other and created the distinctive rocks seen today.

How Needles Form

Starting about fifteen million years ago, the Colorado Plateau was pushed up thousands of feet and rivers, such as the Colorado and the Green, cut down and carved deep canyons. Water, the primary force of erosion, eats away or weathers rock by attacking the cement holding the sand grains together. Moreover, during storms, rushing water knocks loose sand and rocks as it flows down washes causing additional erosion. The water naturally acts faster on areas of weakness within the rock, such as fractures and cracks. The Needles occur in an area with many fractures called joints.

How Joints Form

The joints were formed in two different manners. The first was the Monument uplift, which begins around the Needles District and trends slightly southwest all the way to Monument Valley. This uplift caused brittle, surface rock like the Cedar Mesa Sandstone to crack as it was bent upward, forming a set of joints in a northeast-southwest direction.

A thick salt layer underneath the Needles district, known as the Paradox Formation, is the second cause of joint formation. The salt is flowing slowly toward the Colorado River and dragging the overlying layers with it. As the upper layers became stretched, they also fractured into joints. This action created a set of joints running northeast-southwest. In the Needles area, these two joint sets meet and form square blocks of rock between the joints. As water widened the joints, the squares were sculpted into pillars and spires that are today the Needles of Canyonlands.

THE GRABENS

The grabens in the Needles District of Canyonlands National Park are a system of linear collapsed valleys caused by the movement of underlying salt layers toward the Colorado River canyon. The grabens begin near the Confluence of the Green and Colorado rivers and run roughly parallel to Cataract Canyon for 25 km, veering slightly west before they end. Graben is a German word meaning ditch or grave. In the geologic sense it is a collapsed or down-dropped block of rock that is bordered on its long sides by faults. Grabens are normally associated with "horsts," which are the up-thrown blocks of rock. In German, Horst means aerie, referring to the high nesting sites of predatory birds.

Geologic Processes

The processes that led to the development of the grabens began approximately 300 million years ago in the Pennsylvanian period with the deposition of evaporates (salts) in a shallow inland sea. These deposits, known as the Paradox member of the Hermosa Formation, were later covered by the limestone layers of the upper Hermosa and Rico formations. In the Needles District, the Paradox layer can be 3,000 to 5,000 feet thick.

Sea levels eventually dropped, and white sands blew in from the west, forming large sand dunes. At the same time, red mud and silt was deposited by rain and snow melt from the Uncompahgre Mountain to the east. The resulting red and white beds alternated, forming the lower beds of the Cutler Formation, or the Cedar Mesa Sandstone that is dominant in the Needles District today.

Sediment from a variety of environments continued to accumulate on top of these layers for millions of years. Approximately 60 million years ago, a tectonic plate collision called the Laramide Orogeny created the Rocky Mountains. Shortly after, a regional upwarp called the Monument Uplift caused the sedimentary layers in the Needles to tilt gradually westward. This event also formed joints, or long parallel fractures in the rock, throughout the Needles. In the vicinity of the grabens there are two joint sets: one trending roughly northeast to southwest, and one trending northwest to southeast. Some of these joints became the faults that border the grabens.

Around 10 million years ago, the uplift of the Colorado Plateau gave rise to the Colorado River and its tributaries. As the Colorado river cut its way downward through the rock layers, it carried away millions of tons of sediment towards the Pacific Ocean.

Necessary Ingredients for Grabens Formation

Finally, about 55,000 years ago, the ingredients were in place and the grabens began to form. Four factors have been identified as critical to the formation of grabens:

1) The ability of evaporates to flow plastically. The evaporates in the Needles District are slowly flowing westward towards Cataract Canyon due to the pressure exerted by the rock layers above.
2) The erosion of the Colorado River down to the Paradox Formation, creating a low pressure zone the evaporates are drawn to.
3) The gradual tilt created by the Monument Uplift, which allows gravity to act on the evaporates.
4) The interaction of water with the evaporates, dissolving the salts and facilitating their ability to flow.

The grabens are a very young geologic feature. Graben growth is thought to be a slow process where small, seismically undetectable movement occurs: as little as one inch per year. The grabens continue to drop and slide toward the river today, and are a fascinating feature of the Needles District.

UPHEAVAL DOME

Canyonlands is a place of relative geologic order. Layers of sedimentary deposits systematically record chapters in the park's past. With some exceptions, these layers have not been altered, tilted or folded significantly in the millions of years since they were laid down by ancient seas rivers or winds.

Upheaval Dome is quite a different story. In an area approximately three miles (5km) across, rock layers are dramatically deformed. In the center, the rocks are pushed up into a circular structure called a dome, or an anticline. Surrounding this dome is a downwarp in the rock layers called a syncline. What caused these folds at Upheaval Dome? Geologists do not know for sure, but there are two main theories which are hotly debated.

Salt Dome Theory

A thick layer of salt, formed by the evaporation of ancient landlocked seas, underlies much of southeastern Utah and Canyonlands National Park. When under pressure from thousands of feet of overlying rock, the salt can flow plastically, like ice moving at the bottom of a glacier. In addition, salt is less dense than sandstone. As a result, over millions of years salt can flow up through rock layers as a "salt bubble", rising to the surface and creating salt domes that deform the surrounding rock.

When geologists first suggested that Upheaval Dome was the result of a salt dome, they believed the land form resulted from erosion of the rock layers above the dome itself. Recent research suggests that a salt bubble as well as the overlying rock have been entirely removed by erosion and the present surface of Upheaval Dome is the pinched off stem below the missing bubble. If true, Upheaval Dome would earn the distinction of being the most deeply eroded salt structure on earth.

Impact Crater Theory

When meteorites collide with the earth, they leave impact craters like the well-known one in Arizona. Some geologists estimate that roughly 60 million years ago, a meteorite with a diameter of approximately one-third of a mile hit at what is now the Upheaval Dome. The impact created a large explosion, sending dust and debris high into the atmosphere. The impact initially created an unstable crater that partially collapsed. As the area around Upheaval Dome reached an equilibrium, the rocks underground heaved upward to fill the void left by the impact. Erosion since the impact has washed away any meteorite debris, and now provides a glimpse into the interior of the impact crater, exposing rock layers once buried thousands of feet underground.

Upheaval Dome Today

Whatever the origin of Upheaval Dome, it is the result of erosion of a structural dome. Rock layers now at the surface within the dome were once buried at least a mile underground and are not visible anywhere else in the nearby area. While some call this feature a crater, it is not a crater in the traditional sense of the word, but simply another example of the erosion which created Canyonlands National Park.

DESERT VARNISH

Desert varnish is the thin red to black coating found on exposed rock surfaces in arid regions. Varnish is composed of clay minerals, oxides and hydroxides of manganese and/or iron, as well as other particles such as sand grains and trace elements. The distinctive elements are Manganese (Mn) and Iron (Fe).

The color of rock varnish depends on the relative amounts of manganese and iron in it: manganese-rich varnishes are black; manganese-poor, iron-rich varnishes are red to orange; those intermediate in composition are usually a shade of brown. Varnish surfaces tend to be shiny when the varnish is smooth and rich in manganese.

Desert varnish consists of clays and other particles cemented to rock surfaces by manganese emplaced and oxidized by bacteria living there. It is produced by the physiological activities of microorganisms which are able to take manganese out of the environment, then oxidize and emplace it onto rock surfaces. These microorganisms live on most rock surfaces and may be able to use both organic and inorganic nutrition sources. These manganese-oxidizing microorganisms thrive in deserts and appear to fill an environmental niche unfit for faster growing organisms which feed only on organic materials.

The sources for desert varnish components come from outside the rock, most likely from atmospheric dust and surface runoff. Streaks of black varnish often occur where water cascades over cliffs. No major varnish characteristics are caused by wind.

Thousands of years are required to form a complete coat of manganese-rich desert varnish so it is rarely found on easily eroded surfaces. A change to more acidic conditions (such as acid rain) can erode rock varnish. In addition, lichens are involved in the chemical erosion of rock varnish.

Canyonlands National Park - Wildlife

Though the natural quiet of Canyonlands often creates the impression of lifelessness, many animals live here. Birds, lizards and some rodents are seen most frequently, though seasons and weather play a large role in determining what animals are active.

Desert animals have a variety of adaptations for dealing with the temperature and moisture stresses present in Canyonlands. Most desert animals are nocturnal, being most active at night. This can be an adaptation to both predation and hot summer daytime temperatures. Mostly nocturnal animals include kangaroo rats, woodrats (also called packrats) and most other small desert rodents, skunks, ringtails, foxes, bobcats, mountain lions, bats and owls.

Animals that are most active at dawn and dusk are called “crepuscular.” These times of day are cooler than mid-day. The half-dark makes prey animals less visible, yet visibility is good enough to locate food. Some animals are crepuscular mostly because their prey is crepuscular. Crepuscular animals include mule deer, coyotes, porcupines, desert cottontails, black-tailed jackrabbits, and many songbirds.

A few desert animals are primarily active during the day, or “diurnal.” These include rock squirrels, antelope squirrels, chipmunks, lizards, snakes, hawks, and eagles. Many animals have a temperature range in which they are active, so alter their active times of day depending on the season. Snakes and lizards go into an inactive state of torpor during the winter, are active during the day during the late spring and early fall, and become crepuscular during the heat of summer. Many insects alter their times of activity. Mosquitoes, for example, may be out at night, at dawn, dusk or all day but not at night, depending on the temperatures.

MAMMALS

Almost 50 species of mammal are known to live in Canyonlands. Some animals, like desert cottontails, kangaroo rats and mule deer, are common and may be seen by a majority of visitors. However, many desert animals are inactive during daylight hours or wary of humans, so sightings can be truly special events. Tracks and scat are the most common signs of an animal’s presence.

Canyonlands’ hot climate and lack of water seems to favor small mammals. Because of their size, these animals are less able to migrate, but have an easier time finding shelter and require less food and water to live. Rodents are numerous: there are nine species of mice and rats alone. Beavers, the largest North American rodent, are found along the Colorado and Green rivers. Since the rivers are too swift and broad to dam, beavers burrow dens in the banks.

One animal uniquely adapted to life in the desert is the kangaroo rat. This rat lives its entire life consuming nothing but plant matter. Its body produces water by metabolizing the food it eats. However, even the kangaroo rat is prone to spending the hottest daylight hours sleeping in a cool underground burrow and may even plug the opening with dirt or debris for insulation.

Larger mammals, like mule deer and mountain lions, must cover more territory in order to find food and water, and sometimes migrate to nearby mountains during summer. In Utah, around 80% of a mountain lion’s diet consists of mule deer, so these animals are never far apart. However, unlike mule deer, mountain lion sightings are very rare.

Desert bighorn sheep live year-round in Canyonlands. These animals roam the talus slopes and side canyons along the rivers, foraging on plants and negotiating the steep, rocky terrain with the greatest of ease. Once in danger of becoming extinct, the desert bighorn are now making a tentative comeback that has been fueled by the healthy herds in Canyonlands.

An interesting fall visitor to Canyonlands is the black bear. An unusual sight in the red rock canyons, black bears follow river and stream corridors, like Salt Creek Canyon in the Needles District, that flow from nearby mountains. These visits generally occur in late August and September when prickly pear cacti and hackberry trees bear their fruit. The bears return to the mountains before winter.

REPTILES

Along with cacti and sand dunes, snakes and lizards are icons of the desert. The only reptiles found in Canyonlands are snakes and lizards, underappreciated, sometimes feared, animals that play an important role in the high desert ecosystem. Lizards and snakes help control insect and rodent populations. In turn, both are potential meals for birds and mammals.

All reptiles are cold-blooded or, more accurately, “ectothermic,” regulating body temperature via external sources rather than internal metabolism. A reptile’s metabolic rate is very low, but so are its energy needs. Since keeping warm in the desert does not require much work, reptiles are well adapted to this environment. What energy they do generate can be used for reproduction and finding food instead of heating and cooling.

Of course, there are drawbacks to this lifestyle. Since they don’t pant or sweat, reptiles can’t endure extremely high temperatures without shade. Nor can they endure prolonged sub-zero temperatures. When it’s cold, reptiles hibernate or enter into an inactive torpor. Food stored as fat in their tails helps lizards survive these long periods of inactivity, so losing a tail can be life threatening.

If you visit Canyonlands during the summer, you are sure to see lots of lizards. After birds, these reptiles are the most active animals once daytime temperatures reach 90 degrees and higher. They are usually visible sunbathing on rocks or chasing insects with their lightning-quick reflexes. Lizards found here include the northern whiptail, the desert spiny, and the colorful western collared lizard.

Most of the snakes found in Canyonlands are harmless and nocturnal. All will escape from human confrontations given the opportunity. The midget-faded rattlesnake, a small subspecies of the western rattlesnake, has extremely toxic venom. However, full venom injections occur in only one third of all bites. The midget-faded rattlesnake lives in burrows and rock crevices and is mostly active at night.

AMPHIBIANS

Amphibians may be the last thing people think of when they visit Canyonlands. However, the park is home to a variety of frogs and toads, as well as one species of salamander. Witnessing a chorus of toads may be one of the most memorable experiences canyon country has to offer. It is an awesome event that can fill a canyon with sound, sometimes for hours. Amphibians are animals that have two life stages: a larval, aquatic form and an adult, terrestrial form. This is the difference between a tadpole and a frog. In Canyonlands, amphibians lay their eggs in the potholes, springs and intermittent streams found throughout the park. Swift currents and predation limit survival during the larval stage in bigger rivers like the Colorado.

Adult amphibians may wander away from water, but usually remain nearby and wait out dry periods in burrows. Breeding (and toad choruses) usually occurs on spring and summer nights after significant rainfall. Male frogs and toads do the vocalizing. Females lay long strings of gelatin-covered eggs which, depending on the species, may hatch within hours. Metamorphosis can take weeks, though the Great Basin spadefoot toad transforms to adulthood in as little as 14 days, the quickest of any amphibian.

Lately, news headlines nationwide have featured stories about amphibians with strange mutations like extra or missing limbs, even extra heads. Dramatic population decline and even extinction have also become prevalent problems. The reason for these trends is unclear. However, studies indicate that amphibians are sensitive to a variety of environmental problems.

An amphibian’s water-permeable skin makes it very vulnerable to both air and water borne pollutants. Increases in UV radiation may increase mortality of eggs and tadpoles of some species. Also, the metamorphosis between larval and adult stages is a delicate process that can be affected by environmental changes. Finally, since amphibians range over both terrestrial and aquatic territories, changes in either may affect populations.

Because of this sensitivity, amphibians have become “indicator species,” the health of which can be used to measure the health of an ecosystem. Thus far, neither mutations nor population declines have been observed at Canyonlands, but their importance as an indicator species has made preserving amphibian habitat a priority for the National Park Service.

In Canyonlands, amphibian populations are greatest along small perennial streams like those in Horseshoe Canyon near the Maze, and Salt Creek Canyon in the Needles District. To protect park resources, vehicle use in Horseshoe Canyon was prohibited in the 1970s. Vehicle use in Salt Creek Canyon was prohibited in June 1998 when a U.S. District Court ruled that motor vehicles were causing resource damage to the fragile riparian zone. While that litigation is still ongoing, the park has begun an Environmental Assessment to evaluate several management options for the Salt Creek area.

BIRDS

Birds are the most visible animals in Canyonlands. Even on the hottest summer day, turkey vultures and white-throated swifts circle above the canyons. During winter, juncos and white-crowned sparrows forage around trees and shrubs. While Canyonlands may not be considered a bird watching hot spot, 273 species have been seen in the park, including seasonal and year-round residents as well as migrants.

Canyonlands owes much of this diversity to riparian corridors like the Colorado and Green rivers. In the desert, animal life tends to concentrate around riparian areas because of the abundance of food, water and shelter. During spring and summer, mornings along the rivers are filled with birdsong, including blue grosbeaks, yellow-breasted chats, spotted towhees and canyon wrens. Great blue herons are often seen hunting the shallows for fish, while Cooper’s hawks deftly maneuver through the tangle of trees beyond the riverbanks.

Many birds favor the “upland” areas where grasses, shrubs and small trees dominate. Say’s phoebes, black-throated sparrows and western meadowlarks frequent grasslands. Pinyon jays, scrub jays, juniper titmice and black-throated gray warblers are usually seen in pinyon-juniper woodlands.

Since they are able to fly, it is difficult to generalize about what birds will be found in a particular habitat. However, regardless of habitat or season, the common raven figures prominently in the desert landscape. Ravens are intelligent birds that, according to scientists, display abilities to play and problem-solve rare among animals. This jet-black member of the crow family is also very vocal, using a variety of sounds for communication. Perhaps because of these qualities, ravens have achieved a certain stature in both European and Native American folklore.

Canyonlands monitors bird populations at several selected locations in both upland and riparian areas. Some surveys count all birds, while others focus on birds that actually nest in the park. Findings from these surveys and others like them are used to monitor the health of local bird populations and estimate species richness throughout the country

FISH

The Colorado River and its tributaries are one of the world’s most spectacular river systems. From its headwaters in the mountains of Colorado and Wyoming, the river drops more than two miles on a 1,700-mile journey to the Gulf of California. The water becomes thick with sediment as it passes through the red rock canyons of the Colorado Plateau, and seasonal flow varies greatly. Before dams were built, flows ranged from a few thousand cubic feet per second to nearly 400,000 cubic feet per second.

Historically, only 14 species of fish inhabited the upper Colorado River basin, but over 40 non-native species have been added since the late 1800s. The native fish species in Canyonlands are primarily carp, minnows and suckers, and many are not found anywhere else. These include the Colorado pikeminnow (formerly squawfish), razorback and flannelmouth sucker, as well as humpback and bonytail chub.

There are several different niches within the underwater world of rivers. Razorback suckers and humpback chub prefer turbulent, swift water. Bonytail chub live in calm backwaters and eddies. Pikeminnows spawn in backwaters but roam throughout the river in search of food.

Until recently, pikeminnows were the dominant fish. Growing up to six feet long and weighing over 100 pounds, they could eat almost anything. The pikeminnow was called “Colorado salmon” by early settlers, probably because it migrated up to 200 miles through extreme white water to find its spawning grounds each year.

Today, non-native fish dominate the rivers. One study done at the Confluence in Canyonlands found 95 percent of the fish to be non-native. Carp and channel catfish are the most commonly seen. Carp are native to Asia and were hailed as the greatest food fish ever by the U.S. Bureau of Fisheries. Catfish are known to eat the young of several native species and have played a significant role in the decline of native fish populations.

In the past few decades, the Colorado pikeminnow, razorback sucker, humpback and bonytail chub have all been listed as endangered species.

Canyonlands National Park - Ecology

CANYONLANDS DESERTS

Canyonlands forms the heart of a "high" or "cold" desert called the Colorado Plateau. The arid climate of this area is caused by many factors.

Deserts form when weather patterns or geographic land forms create an environment where lack of water limits biotic productivity. Water may exist in an unusable form such as ice, or may be absent altogether. There are four basic types of desert: high pressure, rain shadow, interior continental and coastal.

High pressure deserts generally form at the middle latitudes (30 degrees) in each hemisphere where warm, dry air masses descend toward the earth's surface. Rain shadow deserts form in localized high pressure zones caused by warm, dry air descending from mountain ranges. The Colorado Plateau is also in the interior of a large continent, far away from significant water sources.

Because of the elevations throughout the region, with a mean of around 3,000 feet and peaks over 12,000 feet above sea level, the Colorado Plateau is also known as a cold or high desert. Though low humidity allows greater penetration of solar radiation, winter air temperatures frequently drop below freezing. In turn, summertime air and especially ground temperatures can reach levels lethal for many organisms. After sunset, the ground rapidly loses heat to the night sky and ambient air temperatures may drop significantly before dawn. Temperature fluctuations of over 40 degrees in a 24-hour period are not uncommon.

Canyonlands receives more precipitation than many other deserts: about 9 inches annually. August is generally the wettest month, as weather systems from the southwest bring brief, intense tropical storms. However, precipitation is highly variable both temporally and spatially. During a single storm, one area may receive significantly more or less water than a neighboring spot less than a mile away.

BIOLOGICAL SOIL CRUST

Biological soil crust is a living groundcover that forms the foundation of high desert plant life in Canyonlands and the surrounding area. This knobby, black crust is dominated by cyanobacteria, but also includes lichens, mosses, green algae, microfungi and bacteria.

Cyanobacteria, previously called blue-green algae, are one of the oldest known life forms. It is thought that these organisms were among the first land colonizers of the earth's early land masses, and played an integral role in the formation and stabilization of the earth's early soils. Extremely thick mats of these organisms converted the earth's original carbon dioxide-rich atmosphere into one rich in oxygen and capable of sustaining life.

When wet, Cyanobacteria move through the soil and bind rock or soil particles, forming an intricate web of fibers. In this way, loose soil particles are joined together, and an otherwise unstable surface becomes very resistant to both wind and water erosion. The soil-binding action is not dependent on the presence of living filaments. Layers of abandoned sheaths, built up over long periods of time, can still be found clinging tenaciously to soil particles, providing cohesion and stability in sandy soils at depths up to 10cm.

Nitrogen fixation is another significant capability of cyanobacteria. Vascular plants are unable to utilize nitrogen as it occurs in the atmosphere. Cyanobacteria are able to convert atmospheric nitrogen to a form plants can use. This is especially important in desert ecosystems, where nitrogen levels are low and often limiting to plant productivity.

Soil crusts have other functions as well, including an ability to intercept and store water, nutrients and organic matter that might otherwise be unavailable to plants.

Unfortunately, many human activities negatively affect the presence and health of soil crusts. Compressional stresses placed on them by footprints or machinery are extremely harmful, especially when the crusts are dry and brittle. Tracks in continuous strips, such as those produced by vehicles or bicycles, create areas that are highly vulnerable to wind and water erosion. Rainfall carries away loose material, often creating channels along these tracks, especially on slopes.

Impacted areas may never fully recover. Under the best circumstances, a thin veneer of cryptobiotic soil may return in five to seven years. Damage done to the sheath material, and the accompanying loss of soil nutrients, is repaired slowly during up to 50 years of cyanobacterial growth. Lichens and mosses may take even longer to recover.

Avoiding these fragile crusts is simple. Always drive or ride on designated roads. Respect road closures and search for places wide enough to pass other vehicles rather than driving over roadside vegetation. When hiking, always walk on marked trails, or on other durable surfaces such as rock or in sandy washes.

EPHEMERAL POOLS A.K.A. POTHOLES

Throughout Canyonlands, naturally occurring sandstone basins called emphemeral pools or “potholes” collect rain water and wind-blown sediment, forming tiny ecosystems where a fascinating collection of plants and animals have adapted to life in the desert. Potholes range from a few millimeters to a few meters in depth, and even the smallest potholes may harbor microscopic invertebrates.

To survive in a pothole, organisms must endure extreme fluctuations in several environmental factors. Surface temperatures vary from 140 degrees Fahrenheit in summer to below freezing in winter. As water evaporates, organisms must disperse to larger pools or tolerate dehydration and the drastic physical and chemical changes that accompany it.

The most extreme conditions exist when a pothole is dry. In addition to the wide temperature fluctuations, ultraviolet light from the sun can damage bodily tissues. Many aquatic organisms are adapted to acquiring oxygen through water and suffer when exposed to air. Pothole organisms have three main ways of dealing with drought.

“Drought escapers” are winged insects, amphibians and invertebrates that breed in potholes but cannot tolerate dehydration (e.g. mosquitoes, adult tadpole and fairy shrimp, spadefoot toads). In some cases, adults live in permanent water sources or on land and travel to temporary pools to mate and lay eggs. If the pool dries out before the young mature, they die. In the case of tadpole, fairy and clam shrimp, adults must lay their drought-tolerant eggs before the pool dries up.

“Drought resistors” (e.g. snails, mites) have a dormant stage resistant to drying out. These animals have a waterproof layer like a shell or exoskeleton that prevents bodily tissues from losing too much water while a pool is dry. By burrowing, these animals are able to seal themselves in the layers of fine mud that often coat the bottom of potholes and form an impermeable crust.

“Drought tolerators” (e.g. rotifers, tadpole and fairy shrimp eggs) are able to tolerate a loss of up to 92 percent of their total body water. This remarkable process, known as "cryptobiosis," is made more unique by the fact that many cryptobiotic species can be rehydrated and become fully functional in as little as half an hour. Cryptobiosis is accomplished by a "command center" that remains hydrated while substituting sugar molecules for water throughout the rest of the body. This transfer maintains the structure and elasticity of an organism's cells during long periods of drought, and enables the organism to withstand the climatic extremes of the desert. In fact, brine shrimp have been hatched from cryptobiotic cysts that endured a flight on the outside of a spacecraft. Many tolerators have only one stage in their life cycle (e.g. egg, larva) that can survive desiccation, and will die if a pool dries up during another phase.

Pothole organisms not only have to endure dry spells, but also must evaluate conditions and decide when to break dormancy. Desert precipitation falls at irregular intervals, and once water enters a pothole there is no guarantee that there is enough for an organism to complete its life cycle. Most organisms living in potholes have very short life cycles, as brief as ten days, reducing the time water is required and allowing them to live in the shallow pools. Even vertebrates such as toads, which are found in other environments, display shorter development times when found in potholes.

A pothole is a unique habitat that is very easily disturbed. Pothole organisms are sensitive to sudden water chemistry changes, temperature changes, sediment input, being stepped on, and being splashed out onto dry land. Human use of pothole water by swimming, bathing or drinking may change the salinity or pH of a pool drastically. More importantly, this change occurs suddenly, unlike the slow, natural changes to which organisms can adapt. Hikers should therefore avoid using water in potholes as well as walking through dry ones.

While these tiny ecosystems may seem unimportant, they can act as an indicator for the health of the larger ecosystems in which they occur. These pools do not have the ability to counteract acids, so the acid rain caused by industrial pollution may be lethal. Pothole health is monitored in Canyonlands in order to track significant changes in our environment.

RIVERS AND STREAMS

Among the natural communities of plants and animals existing in the high desert ecosystem, none is as lush or rich in animal life as the riparian community. Riparian zones are the lush belts of vegetation found along rivers and intermittent streams (which disappear underground periodically along their course). The Colorado River flows through Canyonlands, and one of its major tributaries, the Green River, joins it inside the park at the Confluence. Intermittent streams are found in Horseshoe, Salt Creek and other canyons in the park.

The plants in riparian zones are not adapted to the low-water conditions existing in the surrounding desert. A few of the common shrubs and trees that grow in the lower elevation riparian zones of southeastern Utah are Fremont cottonwood, a few species of willows, seepwillow, tamarisk, water birch, Russian olive, and boxelder.

Wildlife is abundant in riparian zones for a simple reason: all animals need water to survive. Even many desert-dwelling creatures must visit open water sources to drink. Desert bighorn sheep can go for days without drinking, but must eventually find a stream, spring or pothole. Large mammals like mule deer and mountain lions may have huge territories, but must drink at various intervals. Besides using riparian zones as water sources, predators find prey more abundant here.

Some creatures are adapted to live their whole lives in riparian zones adjacent to water, or in the water itself. Beavers are common along the rivers in Canyonlands. Since these waterways are too large to dam, they live in dens in the riverbanks. Muskrats are also common, and a few river otter live along the Colorado River. Ringtails, raccoons, and skunks are most commonly found along streams.

Many insects are confined to water for all or some stage of their lives. Aquatic insects occupy a variety of microhabitats within streams and ponds. Water striders skim the water surface. Caddis fly larvae, in twig- or sand grain-cases, leave trails in the mud as they slowly move across the stream bottom. Black fly larvae use special attachments, like suction cups, to anchor themselves to rocks in waterfalls, filtering smaller organisms from the flow. Some types of mayfly nymphs hold tight to the bottom of loose cobbles sitting on stream bottoms. Diving beetles and water boatmen are more active swimmers.

Riparian zones are rich in bird life. Most songbirds rely on insects for all or part of their diet, especially during nesting season when their protein needs are highest. Larger water birds, including great blue herons, ducks and Canada geese, feed on aquatic plants or prey on aquatic organisms. Osprey and bald eagles primarily eat fish. Peregrine falcons frequently nest on cliffs along the Green and Colorado, and prey on the songbirds and ducks.

If streams were straight chutes with constant downhill drops, flow would have a constant speed and direction. But streams have irregular sides and bottoms, and are steeper in some places than others, so flow varies. Rocks or curves can create backward flow areas behind them called eddies. Rocks mid-stream with water flowing over the top can create holes, where water rushes forward to fill the void behind the obstruction.

Rapids are created when a large amount of rock washes or falls into a river, constricting the flow. Below the Confluence, the Colorado River enters Cataract Canyon, fourteen miles of dangerous white water that, at peak flows, may produce standing waves over twenty feet high. Flow affects the organisms living in the stream, and also affects humans on river trips. Gaining an understanding of flow, called reading the water, is a fascinating and important part of learning to row or paddle a boat.

Canyonlands National Park - Camping

Squaw Flat Campground

Located in the Needles, Squaw Flat Campground is an ideal base camp for day hikes to popular destinations like Chesler Park, Druid Arch and the Joint Trail. There are 26 sites available on a first-come, first-served basis. Bathrooms, fire grates, picnic tables, tent pads and water available year-round. Group size limit is 10 people and 2 vehicles. Maximum RV length is 28 feet.

Fee is $15 per night. Squaw Flat typically fills every day from late March through June and again from early September to mid-October.

Willow Flat Campground

Located at the Island in the Sky, the Willow Flat Campground is a short walk from one of the finest sunset spots in the park: Green River Overlook. Twelve sites are available on a first-come, first-served basis. Sites include picnic tables, fire grates and vault toilets. No water. Maximum RV length is 28 feet. Group size limit is 10 people and 2 vehicles.

Fee is $10 per night. Willow Flat typically fills every day from late March through June and again from early September to mid-October.

The Needles offers three campsites for groups of 11 or more people which may be reserved in advance. The Squaw Flat Group Site can hold up to 50 people and 10 vehicles. The Wooden Shoe Group Site can hold up to 25 people and 5 vehicles. The Split Top Group Site can hold up to 15 people and 3 vehicles. Nightly fees are $3 per person.

Other Camping Options

The Bureau of Land Management (BLM) operates many campgrounds in the Moab area. Some accommodate large groups and may be reserved in advance. For more information, visit the BLM's Moab Field Office (blm.gov).

BACKCOUNTRY CAMPING

Much of Canyonlands is managed as undeveloped land, and the park has become an increasingly popular destination for backcountry travel. Permits are required for all overnight trips in the backcountry. During the spring and fall, demand for permits frequently exceeds the number available. If you plan to visit Canyonlands during peak season, it is recommended that you make reservations well in advance.

Backcountry Campsites and Zones

In order to protect natural and cultural resources and prevent crowding, the backcountry of Canyonlands is divided up into sites and zones, and access to each is limited. There are designated walk-in sites along some heavily traveled hiking trails, mostly in the Needles, for use by backpackers. In more remote areas like the Maze, visitors stay in at-large zones and may choose their own campsites.

WATER

Water is a limiting factor for most backcountry trips in Canyonlands. There are springs scattered throughout the park, mostly in canyon bottoms. There are also large areas, such as the Grabens in the Needles and the entire White Rim bench at the Island in the Sky, where there are no reliable water sources. Obtaining drinking water from the Colorado or Green Rivers is difficult as the water is very silty and hard to purify. Backpacking groups are encouraged to pack in water whenever possible. Many springs marked on topographic maps may dry up during periods of drought. Spring locations and current conditions are available at district visitor centers.

Canyonlands National Park - Contact

Canyonlands is open year-round, 24 hours a day. Each district has its own visitor center with operating hours that differ depending on the season. All visitor centers are closed on December 25th and January 1st.

Island in the Sky: The Island in the Sky Visitor Center is open daily from 9 a.m. to 4:30 p.m., with extended hours March through October.

Maze: The Hans Flat Ranger Station is open daily from 8 a.m. to 4:30 p.m.

Needles: The Needles District Visitor Center is open daily from 9:00 a.m. to 4:30 p.m., with extended hours March through October.

Canyonlands National Park - Directions

Canyonlands National Park
2282 SW Resource Blvd.
Moab, UT 84532

Visitor Information: 435-719-2313

Backcountry Information: 435-259-4351

Educational Fee Waivers: 435-719-2141

Fax: 435-719-2300

Canyonlands is open year-round, 24 hours a day. Each district has its own visitor center with operating hours that differ depending on the season. All visitor centers are closed on December 25th and January 1st.

Island in the Sky: The Island in the Sky Visitor Center is open daily from 9 a.m. to 4:30 p.m., with extended hours March through October.

Maze: The Hans Flat Ranger Station is open daily from 8 a.m. to 4:30 p.m.

Needles: The Needles District Visitor Center is open daily from 9:00 a.m. to 4:30 p.m., with extended hours March through October.

Car: There are two paved entrances into Canyonlands: Highway 313 leads to the Island in the Sky, while Highway 211 leads to the Needles. Roads to the Maze are a mixture of graded dirt and 4WD. These roads may become impassable when wet.

Plane: Commercial airlines serve Grand Junction, CO and Salt Lake City, UT. By car, these cities are at least 2 and 4 hours (respectively) away from the closest park entrance (Island in the Sky). Commercial air service is also available between Denver and Moab.

Bus: Greyhound travels along Interstate 70, making stops at Grand Junction, CO and Green River, UT. Commercial vans/shuttles operate between Moab and Salt Lake City as well as Grand Junction.

Public Transportation: There is no public transportation to Canyonlands.

GETTING AROUND

Travel to Canyonlands generally requires a car. Once in the park, each district offers different opportunities for exploration. The Island in the Sky is the most accessible district and the easiest to visit in a short period of time. All other destinations require some boating, hiking or four-wheel driving to see the area's attractions.

Canyonlands is open year-round, 24 hours a day. Each district has its own visitor center with operating hours that differ depending on the season. All visitor centers are closed on December 25th and January 1st.

Island in the Sky: The Island in the Sky Visitor Center is open daily from 9 a.m. to 4:30 p.m., with extended hours March through October.

Maze: The Hans Flat Ranger Station is open daily from 8 a.m. to 4:30 p.m.

Needles: The Needles District Visitor Center is open daily from 9:00 a.m. to 4:30 p.m., with extended hours March through October.